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The antimalarial activities of crude extracts and 17 fractions from the partition of 80%-methanolic extracts of three plants (the stem bark of Croton mubango, the stem bark of Nauclea pobeguinii and the leaves of Pyrenacantha staudtii) used as antimalarial remedies in the Democratic Republic of Congo were studied both in vitro (against Plasmodium falciparum) and in mice infected with Pl. berghei berghei. The toxic effects of dried aqueous extracts of the plants were also investigated, in uninfected mice. The most active crude extracts in vitro, with median inhibitory concentrations (IC50) of <1 μg/ml, were found to be the methanolic and dichloromethane extracts of C. mubango, and the dichloromethane extracts of N. pobeguinii and Py. staudtii. The aqueous extract with the most antimalarial activity in vitro was that of C. mubango (IC50=3.2 μg/ml), followed by that of N. probeguinii (IC50=5.3 μg/ml) and then that of Py. staudii (IC50=15.2 μg/ml). Results from the in-vivo tests of antimalarial activity showed that, at a daily oral dose of 200 mg/kg, all the dichloromethane extracts, the petroleum-ether, chloroformic, ethyl-acetate and residual water-soluble fractions from C. mubango, and the chloroformic, ethyl-acetate and n-butanolic fractions from Py. staudtii produced >80% chemosuppression of the parasitaemias by day 4. The aqueous extracts of C. mubango and N. probeguinii produced a slightly lower but still significant inhibition of parasitaemia (60%–80%) whereas that of Py. staudtii only suppressed the day-4 parasitaemias by 37%. The dried aqueous extract of the stem bark of C. mubango showed some signs of toxicity in mice, with median lethal doses (LD50) of 350 mg/kg in the female mice and 900 mg/kg in the male. The extract significantly increased the serum concentrations of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) in mice of both sexes, but had no effect on the blood levels of creatinine or urea. No significant toxic effect was observed for the dried aqueous extracts of N. pobeguinii and Py. staudtii (LD50 >5 g/kg). Neither of these extracts affected the serum concentrations of GPT or the blood concentrations of creatinine and urea, although the N. pobeguinii extract did increase the serum concentration of GOT. [ABSTRACT FROM AUTHOR]

Implementation of pharmacovigilance (PV) systems in resource-limited countries is a real endeavor. Despite country- and continent-specific challenges, the Democratic Republic of the Congo (DRC) has been able to develop one of the most active PV systems in the sub-Saharan Africa. The World Health Organization (WHO) regional Office identified the DRC experience to set up a PV system for antimalarial drugs safety monitoring as a 'best practice' that needed to be documented in order to help DRC improve its PV system and to be scaled up in other African countries. In response to the WHO request, a best practices and bottlenecks analysis was conducted in 2015. This analysis was updated in 2018 in the light of the minimum requirements of the WHO to set up a PV system taking into account other guidance for PV systems. The following themes were retained for analysis: (1) creation of the national PV center; (2) implementation of PV in the health system; (3) data collection and analysis; (4) collaboration with public health programs; (5) collaboration with the National Regulatory Authority. Lessons learnt from the DRC experience show that it is possible to implement PV systems in order to promote patients' safety in resource limited sub-Saharan African countries with no guaranteed funding. The ability of national PV centers to collaborate with Public health stakeholders, including public health authorities at all levels as well as public health programs, and to use existing health information systems are considered the main key to success and may substantially reduce the cost of PV activities., Competing Interests: Conflict of interest statement: The authors declare that there is no conflict of interest.

Background: In early 2016, there was a Yellow Fever (YF) outbreak in Central Africa with several deaths reported from Angola and the Democratic Republic of Congo. Due to a shortage in vaccine supply, fractional dosing (0.1 ml) of 17DD Yellow Fever Vaccine (YFV) was proposed in preventive vaccination campaign in Kinshasa in August 2016. A Pharmacovigilance surveillance at community level was implemented to track Adverse Events Following Immunization (AEFIs). The objective of this study was to describe AEFIs as captured from community-based pharmacovigilance and to compare the safety profile of the fractional dosing of YFV between gender., Methods: PV information sessions were organized in churches, academic institutions, and pediatrician, obstetrician and friend networks. Prior to data collection, education about AEFI was provided through face-to-face discussions, phone calls, SMS and WhatsApp messages. Individuals reported AEFIs though the above communication channels to assigned individuals. Reported AEFIs were entered into VigiFlow and extracted for statistical analysis using Stata 12. Only vaccinees who received fractional dose (subjects from the age of 2-year-old and non-pregnant women) were included in analysis. Proportional t-test was used to compare AEFI preferred terms among males and females., Results: A total of 4020 subjects reported 5409 AEFIs. Reporters were mostly males (54.9%) with an average age of 26 ± 10.7 years. Fever and injection site pain were the most reported systemic and local AEFI respectively. The safety profile was similar between gender although females reported more diarrhea and dizziness whilst males reported more asthenia (P < 0.001). Five individuals reported serious AEFIs. Among them, 4 were less-immunocompetent., Conclusion: Fractional dosing of 17DD YFV has a good safety profile, which is similar between gender. These findings complement the documented immunogenicity profile to support recommendation of fractional dose of YFV for outbreak control., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Physalis angulata L., an annual herb from the Solanaceae family, is widely used in popular medicine in tropical countries to treat a variety of diseases. Two products, (X) and (Y), were isolated from a crude CH2Cl2 extract of dried Congolese Physalis angulata L. plants and crystallized from acetone for structure elucidation. Compound (X) corresponds to a physalin B dimer acetone solvate hydrate (2C28H30O9·C3H6O·0.22H2O), while compound (Y) crystallizes as a mixed crystal containing two physalin B molecules which overlap with 5β,6β-epoxyphysalin B, also known as physalin F, and one acetone molecule in the asymmetric unit (1.332C28H30O9·0.668C28H30O10·C3H6O). Antiplasmodial activity, cytotoxic activity and selectivity indices were determined for crude extracts and the two isolated products (X) and (Y).